Data stream mirroring provides a duplication of a stream of data packets to an alternate destination in addition to a primary destination. Mirroring may be employed for debugging and diagnoses of network traffic anomalies, security and surveillance, and as a failover or redundancy path for critical data. Mirroring involves identification of a source stream, typically designated as a router port and optionally with filtering to restrict particular source or destination addresses, for example. The mirroring setup also designates a mirroring destination as the recipient of the mirrored stream, resulting in a duplicate packet for each packet in the identified source stream.
Remote Switch Port Analyzer (RSPAN) and Encapsulated Remote Switch Port Analyzer (ERSPAN) are efficient, high performance traffic monitoring systems. They duplicate network traffic to one or more monitor interfaces as it transverse a switch. While the term RSPAN is used throughout the application, it should be appreciated that ERSPAN could also be used and the terms are used interchangeably throughout. RSPAN is used for troubleshooting connectivity issues and calculating network utilization and performance, among many others. RSPAN allows a user to monitor traffic from source ports distributed over multiple switches. RSPAN works by mirroring the traffic from the source ports of an RSPAN session onto a Virtual Local Area Network (VLAN) that is dedicated for the RSPAN session. This VLAN is then trunked to other switches, allowing the RSPAN session traffic to be transported across multiple switches. On the switch that contains the destination port for the session, traffic from the RSPAN session VLAN is simply mirrored out the destination port. ERSPAN brings Generic Routing Encapsulation (GRE) for all captured traffic and allows it to be extended across Layer 3 domains.
Fabric Attach (FA) is an enhanced implementation of Shortest Path Bridging (SPB)) technology that simplified operations through access layer only network provisioning. FA delivers a “Zero-Touch-Core” that virtually eliminates the chance of core network misconfiguration. It allows simple and secure deployment for any type of network service without the need to make any configuration changes on intermediate/core nodes, even in environments where clients roam. These same benefits are also available to network elements or hosts that are not SPB-capable. Any FA capable device (a switch, server, Access Point (AP), Internet Protocol (IP) Phone, etc.) can be securely connected to the network, be authorized for a network service, and attach to the appropriate network service instance—all automatically and based on policy. This enables Fabric Attach devices to come straight out of the box and onto the network with “Zero Touch”.